Earth may be trapped in an abnormal bubble of space-time that is particularly void of matter. Scientists say this condition could account for the apparent acceleration of the universe's expansion, for which dark energy currently is the leading explanation.
The image is from NASA, a Chandra X-ray photograph showing Cassiopeia A, the youngest supernova remnant in the Milky Way.
Dark energy is the name given to the hypothetical force that could be drawing all the stuff in the universe outward at an ever-increasing rate. Current thinking is that 74% of the universe could be made up of this exotic dark energy, with another 21% being dark matter, and normal matter comprising the remaining 5%.
Until now, there has been no good way to choose between dark energy or the void explanation, but a new study outlines a potential test of the bubble scenario.
If we were in an unusually sparse area of the universe, then things could look farther away than they really are and there would be no need to rely on dark energy as an explanation for certain astronomical observations.
But there's a problem with this void idea. It means we live in a special place.
it negates a principle that has reigned in astronomy for more than 450 years: namely, that our place in the universe isn't special.
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"This idea that we live in a void would really be a statement that we live in a special place," Clifton told SPACE.com. "The regular cosmological model is based on the idea that where we live is a typical place in the universe. This would be a contradiction to the Copernican principle."
Kevin Kelly, co-founder and Editor-at-Large of Wired, takes a look at the Narrow Gates of Inevitability
I am a child of science fiction, so I have not come to these heretical notions easily. But I changed my mind looking at our results so fare. The more we investigate the conditions for life --- any life – to spontaneously organize itself, the more remarkably narrow those conditions appear. Life requires a goldilocks’ touch – not too hot not too cold; not too ordered, not too chaotic; not too strong, not too weak. Up and down the scale of reality, from cosmic constants like force of gravity, to the exact size of our planet, to the temperature that ice molecules melt – all these values and hundreds more turn out to hover around sweet spots that permit the dynamic balance of life as we know it to thrive. In fact the dynamic balance of life, persistently hovering between order and disorder requires sweet spots.
Outside of this very thin corridor of parameters, life-as-we-know-it is denied. The more science investigates extropic systems via models and simulations, the more sweet spots it discovers life depends on. When all these alignments are exposed and listed, the confinement of life becomes quite clear.